Sixteen men and six women were sent to two hospitals, according to the local newspaper.
Ten of them were in a stable condition as of 6 p.m. local time (10:00 GMT).
The paper posted a photo of a blooded man, allegedly a driver for the local television channel, RTHK, who sustained a head injury.
Police fired tear gas and rubber bullets at protesters after they stormed government buildings. The Legislative Council put off indefinitely a second reading of the bill, which will make it easier to extradite fugitives to China.
Over a million demonstrators took to the streets in Hong Kong over the weekend in what was the biggest protest since the former British colony was handed back to China in 1997.